[PATCH v2 0/6] Enable setexpr command to print cpu-list like bitmaps

[Heinrich Schuchardt]

On 12.12.23 09:52, lukas.funke-oss at weidmueller.com wrote:
> From: Lukas Funke <lukas.funke at weidmueller.com>
>
>
> This series enables the 'setexpr' command to print "cpu list"-like
> bitmaps based on the printk format specifier [1].
>
> One use-case is to pass cpu list [2] based kernel parameter like
> 'isolcpu', 'nohz_full', irq affinity or RCU related CPU parameter to
> the kernel via a separate firmware variable without exposing the
> 'bootargs' variable to directly.
>
> Example:
>
> setexpr isolcpu_bootarg=%32pbl $myCPUisolation

I applied your patches on top of origin/next but your example simply
does not work:

=> setenv myCPUisolation 123456789abcdef0
=> setexpr isolcpu_bootarg=%32pbl $myCPUisolation
## Error: illegal character '='in variable name "isolcpu_bootarg=%32pbl"

This produces some output:

=> setexpr a fmt '%32pbl' 64; echo $a
6

But the result is completely unexpected. Number arguments in U-Boot are
always hexadecimal. So the output should be

2,5-6

Best regards

Heinrich

> && env set bootargs "$isolcpu_bootarg"
> && bootm
>
> [1] https://www.kernel.org/doc/Documentation/printk-formats.txt
> [2] https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
>
>
> Changes in v2:
> - Add bitmap format specifier to documentation
>
> Lukas Funke (6):
>    sandbox: add generic find_next_zero_bit implementation
>    linux: bitmap.h: add 'for_each_set_bitrange' iteration macro
>    test: cmd: setexptr: Add tests for bitmap string format
>    doc: printf() codes: Add bitmap format specifier
>    lib: vsprintf: enable '%*pb[l]' format specifier
>    cmd: printf: forward '%p' format string specifier
>
>   arch/sandbox/include/asm/bitops.h | 16 ++++++-
>   cmd/printf.c                      | 29 ++++++++++++
>   doc/develop/printf.rst            |  6 +++
>   include/linux/bitmap.h            |  7 +++
>   lib/vsprintf.c                    | 75 +++++++++++++++++++++++++++++++
>   test/cmd/setexpr.c                |  9 ++++
>   6 files changed, 140 insertions(+), 2 deletions(-)
>